# Tag Info

8

While the 4004 and Z80 were available, they were both unlikely to be used in handhelds where low part count, cost and battery life were important. There were families of 4-bit and 8-bit microcontrollers from the 1970s that have been mostly forgotten - these usually had on-chip ROMs so after developing your program on a relatively expensive emulation system ...

1

The 'black blob' is chip-on-board (COB) technology. The technique is still used today and the semiconductor die(s) are directly placed directly on the board and interconnected. The black substance is used to protect the fine wires from damage. Now you know the term there are many resources around you can find, for example the following looks like a good ...

0

You are right. Edge triggering is just a much narrower form of level triggering, and depends on timing. Inside an edge-triggered device, the changing clock edge is just turned into a pulse which causes it to accept the inputs: a level trigger! But the level trigger is very short. It must be so short that the outputs are not able to propagate back to the ...

2

What's important about a clock signal? All of it, of course! :) But seriously, there are many aspects to a clock signal and it is difficult to limit it down to just a couple of things. It also greatly depends on what you are doing with it. Below, I will give you some aspects to consider: Frequency: Some applications require more accurate frequency ...

2

I see nothing in the circuit that should stop multiple same-clock-cycle propagations if the circuit is fast enough? This is referred to as a hold time violation, and they are terribly fatal to a circuit. It doesn't happen because ASIC creators run expensive timing analysis software to check every single path in the design to make sure that the path is ...

1

The interval between clocks allows signals to stabilize before the rising edge of the next clock. Between clock active edges, there may be logic devices that are not clock synchronized and need a few nano-seconds to settle on an output value before the next clock edge arrives on the logic devices that the non-synchronized devices feed. This is just an ...

0

Yes, Douglas W. Jones writes good tutorials. I recommend getting an off-the-shelf motor driver and an off-the-shelf stepper working first, before trying to build some custom motor driver or some custom-wound motor. The stuff that goes between the pins of the microcontroller and the wires of the motor is called the "motor driver", also called the ...

0

If you really only need 7 segments (and no decimal point or such), then you could have each PCF8574AN drive a pair of 7 segment displays, one common cathode, and one common anode (some manufacturers build both variants). You could then use e.g. pin 7 as the cathode/anode pin: If it’s 0, an 1 in the other bits will light the corresponding segment of the ...

1

The load is in fact equivalent to single TTL input. TTL family has open emitter inputs. That Base-emitter junction is horizontal diode in picture. 3 diodes in series are base-collector of NPN transistor followed by 2 base-emitter junctions cascaded. As The Phantom noted, you can use simple TTL buffer input as load. You can see typical internal circuit for ...

0

The most expensive part will be the switch. What switch/dial do you already have? It may be that a $0.50 potentiometer, and a$2 Attiny85, will actually be cheaper than an actual three-way mechanical rotary switch! The Attiny85 (and friends) can run Arduino sketches if you have a USB programmer, and it has an analog input for the pot, and several digital ...

2

Lets not forget that, aside from MAKING the actual IC (covered in a very humorous and accurate fashion already here) you also need to know how to design circuits that lend themselves to IC implementation. You'll not find very many passive components within an IC - they are not so well behaved and typically take up a disproportionately large area. Instead, ...

0

An official/commercial Arduino would be overkill for this. So you can go with a smaller, bare bones Arduino clone. Some are as simple as a ATMega and a few component parts. The other option is using an Attiny with arduino code, essentially the same thing, but with a smaller MCU. A msp430 could just as easily do the same. Honestly, any microcontroller could ...

1

If I'm understanding your question right, you can accomplish this with a simple (and I mean simple!) circuit. Assuming your "dial device" operates like a switch, here is a circuit which assumes you just have a 2 state dial. Adding more LEDs is very simple; just add another LED to a different output of the dial switch. If this isn't what you were ...

13

This question is equivalent to asking, I want to build a 747 jetliner in my basement, but I need to do it only from drawings and raw materials. The fact that a question like this does get asked really just shows how little appreciated the complexity of what is involved in modern semiconductor manufacturing and the pure inventiveness that it entails. The ...

5

Check the datasheet for Absolute Maximum Ratings. For normal use you want to look at: DC Output Source or Sink Current per Output Pin, IO For VO > -0.5V or VO < VCC+ 0.5V ± 25mA Keep well below that value, say 20mA max, then you are safe. You'll have to calculate a series resistor for that as the device will be fried if you exceed the ...

1

Look in the Absolute Maximum Ratings section for information on the MAX current that the part can safely source or sink. In another part of the data sheet you should find the Recommended Operating Conditions where the output low voltage and output high voltage levels are specified at particular sink and source current levels. These will normally also be the ...

1

I do NOT think there is a single chip solution neither. However doing this with an FPGA-based platform is certainly doable. As already mentioned the Digilent Atlys Board could be an alternative since you have there 2 in/ 2 out HDMI ports. In case you consider working with FPGAs: First, I would suggest to start with the design of a HDMI transmitter and ...

3

A more appropriate question is "What and how are electronic circuits combined to create microprocessors?" Electronic circuits aren't implanted onto microprocessors. Microprocessors are comprised of electronic circuits. Resistors, capacitors, and inductors are passive analog circuit elements. The development/invention/discovery of semiconductors gave way to ...

57

No big deal really. First you get a pile of silicon. A bucket of ordinary beach sand contains a lifetime supply if you're going to make your own chips. There is lots of silicon on this planet, but it's mostly all so annoyingly bound up with oxygen. You have to break those bonds, discard the non-silicon stuff, then refine what's left over. You need very ...

3

You definitely won't be able to get this done at home! Manufacturing chips is a complex process involving lots of precise, expensive, complex machinery. If you are interested in developing your own microprocessor, start by learning VHDL or Verilog and getting it working on an FPGA. Then you might consider learning chip design at a transistor level and ...

7

There are people doing this at home, but it's a bit like trying to build a space program in your back garden. It's much harder than e.g. a 3D printer, and involves some nasty chemistry and astonishingly high precision engineering. https://code.google.com/p/homecmos/ , although they've not actually produced a device yet. ...

1

The simple answer is "no, there is no single-chip solution." The reasons are already mentioned by Chris Stratton: - The two signals are not in sync, so at least one of the frames need to be re-buffered (typically, both will need to be, to be able to do the blend/overlay.) - HDMI in a living room typically carries encrypted signals, so you need to also do ...

0

You need an isolating transformer to pass power between isolated circuits. Nothing else will cut it. You could use a large transformer with the 50Hz mains, or perhaps some sort of switch mode power supply circuit. Even a 5V boost/buck type circuit could work if you find a suitable isolated low power transformer.

2

The Diodes are the Mosfet body diodes. They are internal, and part of how the mosfet works. The Mosfet themselves are used as simple level shifters on the I²C clock (SCL) and data lines (SDA) enable I²C communication with microcontrollers operating at the same voltage as VIN (2.5–5.5V) i2c, an open drain protocol, requires pull-up resistors. The value of ...

1

Another non-microcontroller option is a 4017 decade counter. This chip has 10 output pins. Each pin goes high, in turn, as you pulse the clock. In order to make it only pulse 3 outputs, just connect the 4th output pin to the Reset pin. As soon as 4 goes high, the counter will reset back to 1. An astable 555 is a nice adjustable clock source for lower ...

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